Testicles

[z Peronówki]

I fully agree with Letty - sure missing tescticles have genetic reasons but it is not posible to say who is responsible for it. There are many reasons so the only way the breeders found out is not to use males with missing tescticles for breeding. And keep eye on lines where it appears more often than by other dogs...
Of course if there is a male (or female) which gives more kryptorchid puppies than the average rate (and there are kryptorchid dogs in every litter) than you can say he/she is carring "defect genes". But there rest is juest the question of probability...